In the manufacture of plastics bags using reclosable fasteners the zipper which is used and which carries male and female profiles is wound on reels, from which it is unwound for guidance towards the bag-making apparatus. Currently, when a reel of zipper is exhausted, it is necessary to switch over to another reel. This can be a time-consuming operation, requiring the new zipper to be correctly fed into and established within the bag-making apparatus.